Quantum Data 801GC, 801GF, 801GX manual Htot = Hres / 1 Blanking x Hrat

•A spec sheet may give you pixel counts for the number of active pixels as well the hori- zontal sync front porch, pulse width and back porch. Add all four numbers together to get HTOT.

•A spec sheet may give you a dot clock or pixel rate. Divide this rate by the horizontal rate and round the result to the nearest even integer.

•A spec sheet may give you the number of horizontal active pixels and express the hori- zontal blanking time in micro-seconds. The value for HTOT can be calculated with this formula:

HTOT = HRES / (1 - (Blanking x HRAT))

Where Blanking is in units of seconds and HRAT is in units of Hz. Remember to round the re- sult to the nearest even integer.

The HSPD parameter sets the number of pixels be- tween the end of active video and the beginning of the horizontal sync pulse. Many spec sheets refer to this parameter as the “Horizontal Sync Front Porch.” If your spec sheet gives you the horizontal front porch in units of pixels, use this value for HSPD. Here is another way to calculate the value for HSPD from other data on your spec sheet:

•A spec sheet may give you the horizontal front porch in micro-seconds. The value for HSPD can be calculated with this formula:

HSPD = HTOT x HRAT x Front Porch

Where Front Porch is in units of seconds and HRAT is in units of Hz. Remember to round the result to the nearest integer.

The HSPW parameter sets the width of the horizon- tal sync pulse in units of pixels. Many spec sheets refer to this parameter as “Horizontal Sync Pulse Width.” If your spec sheet gives you the pulse width

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